Bolt lug contact and amount of free float

Tac-O

Well-Known Member
Joined
Apr 28, 2019
Messages
1,550
Location
Utah
I have two questions for everyone.

I was recently reading something about checking bolt lug contact for squareness. The instructions were to put sharpie on the rear face of the boot lugs, then cycle the bolt 10 or so times. The amount of sharpie worn off each lug should be the same.

I did this and the picture shows each lug. This is a Tikka bolt. Does this look good enough?

The other question is, how much free float do I really need on my foreend? I have a .30-06 t3x superlite that's bedded into a Boyd's laminate prairie Hunter stock, with torque set to 65in/lbs. I have a little less than 1/16" free float. Is this enough? Do I need more to be sure the barrel isn't hitting the foreend during recoil?

Thanks!
 

Attachments

  • IMG_20200528_180713044.jpg
    IMG_20200528_180713044.jpg
    425.6 KB · Views: 364
  • IMG_20200528_180629764.jpg
    IMG_20200528_180629764.jpg
    525.2 KB · Views: 339
Those lugs look good. As far as floating the barrel, the old rule of thumb was a folded dollar bill should slide freely and that's probably fine but I usually like at least a business card to be able to slide freely.
 
You still fighting with the tikka ;)
Always!!! I'm 95% sure my gun, scope, rings, and loads are solid, and I suck. I'm just always thinking of various things to check equipment wise, to move that up to 99% confidence that I suck 😂

Here's three targets from a few days ago.the first is obviously my sight in target, second is the best, third is the high left low right string. I'm wondering if that last target string was due to scope parallax error or if it was me getting tired and twitchy. BTW, all rounds were strings of 4 or 5 then cool. Barrel only ever got pretty warm but still touchable. It's definitely not a heat stringing issue.
 

Attachments

  • IMG_20200526_204119939.jpg
    IMG_20200526_204119939.jpg
    315.4 KB · Views: 295
  • IMG_20200526_204111909.jpg
    IMG_20200526_204111909.jpg
    372.8 KB · Views: 299
  • IMG_20200526_204145960.jpg
    IMG_20200526_204145960.jpg
    309.1 KB · Views: 306
I wish I could give you some useful tips. I mostly just shoot heavy barrels. The last Sporter weight barreled rifle that I was serious about took me a while to master so I'm probably not the best to give advice about those. I can tell you that particular rifle was very sensitive to powders that created much barrel heat and it took me along while to figure that out. Of course, it was a hammer forged Sporter weight barrel, go figure. It so happened that RL17 was the coolest power I had to run in it and it worked. I'm not suggesting that you run RL17 or that it's a great powder but it was what I had. I guess my point is that hammer forged Sporter weights can be difficult but not impossible to get what you want out of them. This may have not helped you at all, I'm just thinking out loud, LOL
 
I have two questions for everyone.

I was recently reading something about checking bolt lug contact for squareness. The instructions were to put sharpie on the rear face of the boot lugs, then cycle the bolt 10 or so times. The amount of sharpie worn off each lug should be the same.

I did this and the picture shows each lug. This is a Tikka bolt. Does this look good enough?

The other question is, how much free float do I really need on my foreend? I have a .30-06 t3x superlite that's bedded into a Boyd's laminate prairie Hunter stock, with torque set to 65in/lbs. I have a little less than 1/16" free float. Is this enough? Do I need more to be sure the barrel isn't hitting the foreend during recoil?

Thanks!
You look like you're doing just fine to me
 
I wish I could give you some useful tips. I mostly just shoot heavy barrels. The last Sporter weight barreled rifle that I was serious about took me a while to master so I'm probably not the best to give advice about those. I can tell you that particular rifle was very sensitive to powders that created much barrel heat and it took me along while to figure that out. Of course, it was a hammer forged Sporter weight barrel, go figure. It so happened that RL17 was the coolest power I had to run in it and it worked. I'm not suggesting that you run RL17 or that it's a great powder but it was what I had. I guess my point is that hammer forged Sporter weights can be difficult but not impossible to get what you want out of them. This may have not helped you at all, I'm just thinking out loud, LOL

Why does the hammer forging part matter... Just curious. it's the first time I've heard someone mention hammer-forged barrels being hard to get to shoot. Tikka and Ruger are both Hammer forged, and their barrels are great. I'm not sure about Ruger, but I've heard quite a few people stay they had to get their Tikka barrel really dirty for it to start shooting well andconsistently.

Yes I think the hardest part with mine, if I am the weak link, is getting it to recoil same way every time. I should have hit the easy button and gotten my stainless Tikka in a 6.5 creedmoor instead 😂🙄
 
Mine was a Remington hammer forged barrel. Im not saying that absolutely all of them will be temperamental but I believe mine might just have had quite a bit of stress in the metal. Any time I used a powder with it that warmed the barrel, even on the first shot it would start to walk. When I swapped to a powder that only got the barrel warm after the 3rd shot, it seemed to print 3 shot groups better. And would print them in succession to the same poi after a long cool. The funny thing with that rifle is that with the hotter burning powders, I could fire one shot, put the rifle up overnight, go back the next day and put another round through the same hole from the prior day. And it would repeat that to the next day. If I tried a three shot group in one day it would shoot about MOA sized groups, which wasn't bad but I wanted just s little better than that. Any way, it looks like you are doing something right with what you have going on. None of my troubles with the rifle I mentioned may even have any thing to do with your situation. I have have a heavy hammer forged barrel that also shoots really well. I just think a light contour hammer forged barrel may be more susceptible to walking with heat. Again, I'm not saying that they won't easily shoot moa or better 3 shot groups. But it may be a little more challenging with them getting sub 1/2 moa groups vs a heavy barrel. And sub 1/2 moa groups are great but really may not even be needed depending on how far you are shooting.
 
Why does the hammer forging part matter... Just curious. it's the first time I've heard someone mention hammer-forged barrels being hard to get to shoot. Tikka and Ruger are both Hammer forged, and their barrels are great. I'm not sure about Ruger, but I've heard quite a few people stay they had to get their Tikka barrel really dirty for it to start shooting well andconsistently.

Yes I think the hardest part with mine, if I am the weak link, is getting it to recoil same way every time. I should have hit the easy button and gotten my stainless Tikka in a 6.5 creedmoor instead 😂🙄
Hammer forged barrels can have some stress induced into the metal from that process. That can cause shots to walk with heat. It would be more noticeable on a lighter contour barrel.
 
Hammer forged barrels can have some stress induced into the metal from that process. That can cause shots to walk with heat. It would be more noticeable on a lighter contour barrel.

I understand that. From what I've see in my groups, I can't find any definitive walking when the barrel warms up. On the best group, I had the barrel pretty warm on shots 4, 5, 8, and 9 and they landed close to zero.

I think I may get to go to the range again today. I have 20 of the same load worked up, same number of firings on brass. Since I won't have to do any zeroing shots, my plan is to shoot two 10 round groups to see if the same pattern emerges on the second group, but of course letting the barrel cool after 4 or 5 shots.

What I'll be concentrating the most on to hopefully fix that large stringing is:
1. consistent shoulder placement of the recoil pad - sounds easy, but at the bench it seems having identical placement each time helps
2. consistent body position to make recoil as consistent as possible
3. extra focus on second group when I'm starting to feel tired - I concentrated extremely hard on shots 4-8 on the worst group because I could feel I was getting tired and they were better than the first 3
4. parallax error - I've always been under the impression that you're eye is positioned correctly when you have the shadow around the edges of the image removed, so this is what I check for. I can move my head around slightly side to side and still not have any shadow show up but I'm not good at detecting any reticle float when doing this (if there is any). So, I'll be focusing on getting my eye into the exact same position each time. My scope is fixed parallax at 150yds, so I'm not sure if parallax error could result in that large amount of shot dispersion you see in the stringing group.
 
Your barrel could be walking but ime it's just shooting technique.
Only apply pressure with you pinky and ring finger, keep thumb and middle finger relaxed. Squeeze what it takes to hold a full bottle of beer with your pinky and ring finger.
Use scope shadow to remove parallax. Yes a fixed parallax can have a lot of error if your eye is misaligned.
Focus on your reticle, not the target as you break the shot.
Lay on the ground and preload your bipods with a tear bag instead of on the bench
These are things that I find help me
 
Warning! This thread is more than 5 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top